Ground anchors are well known and widely used in landscaping operations, for example to anchor a transplanted tree in an upright position during a period of time following transplantation until the roots of the tree grow to suitably anchor the tree without need for additional support. In such a role, a generally planar, elongate ground anchor is typically secured to an anchor cable and driven into the ground by a driving rod or tool so that the cable remains above the ground, and the ground anchor is in an insertion position basically parallel to a direction the anchor was driven into the ground. The ground anchor often has a curved or slanted top end, and when the anchor cable is pulled upward, away from the ground, the ground anchor moves to an anchor position, wherein the anchor is essentially perpendicular to the direction the anchor was driven into the ground, thereby securing the cable against further movement away from the ground. A support rope or line may then be secured between the anchor cable and the tree to secure the tree.
Modern ground anchors have been designed to minimize manufacturing costs while achieving adequate performance. For example, in U.S. Pat. No. 5,171,108 to Hugron, a ground anchor is disclosed that includes a curled leading or drive end having a throat that receives a specialized tip of a drive rod to position the anchor under ground. Hugron also includes a cable passing through the anchor to form a loop above the throat so that the drive rod may pass through the loop and then into the throat. Securing the rod along the anchor within the loop of the cable restricts the anchor from moving out of a desired alignment in the event the anchor impacts a rock as it is driven into the ground. However, because the anchor of Hugron must have the cable loop to guide the drive rod, the anchor is limited to a cable with adequate rigidity to form the loop, and the loop must be secured in a fixed position and of proper size to receive the drive rod. Consequently, a heavy cable must be used, and a simple single-strand wire secured by a common knot or tight winding to the anchor body may not be used. Additionally, Hugron shows a curled top end that curls away from a central body of the anchor in a direction opposed to a direction of curvature of the rod receiving throat. Therefore, as the ground anchor is pulled from the insertion position to the anchor position, the curled throat resists such movement to an alignment transverse to the direction of insertion, and may actually prevent movement to a full anchor position. Accordingly, while the ground anchor of Hugron is essentially a single-piece construction of modest cost, it has the aforesaid limitations inherent to its structure.
A somewhat similar ground anchor is shown in U.S. Pat. No. 5,123,799 to Miller, wherein a tail flap extends away from a body of the anchor to position the anchor in the anchor position when an anchor strap is pulled. While an offset drive rod receiving socket in Miller is positioned to extend away from the body of the anchor in the same direction as the tail flap and hence does not interfere with movement of the anchor from the insertion to the anchor position, the socket is nonetheless a complicated structure that must be welded, or otherwise secured offset to a center line of the body of the anchor. Therefore, the ground anchor of Miller necessarily involves substantial manufacturing costs. A further example of an even more complicated ground anchor is shown in U.S. Pat. No. 5,175,966 to Remke et al., wherein a stepped drive rod receiving notch in a top or guide end of the anchor is positioned between two planing wings that direct the anchor after insertion into the anchor position. Instead of having the drive rod pass to a drive end of the anchor as in Hugron and Miller, the specialized drive rod of Remke et al. includes a "U"-shaped groove for engaging three bearing edges of the anchor at the guide or top end in order to keep the anchor in coaxial alignment with the drive rod during insertion into the ground. While efficient, the complications of requiring three mating edges between the anchor and rod along with a need for the anchor body to be adequately strong to avoid deflection during insertion into the ground necessarily increase manufacturing costs.
Additionally, known ground anchors such as those described provide the user little or no opportunity to extract the anchor after use, without bending the anchor or breaking the attachment structure that secures the anchor cable to the ground anchor. Accordingly, there is a need for a ground anchor that is of simple construction, yet of durable application, and that may be re-used in specific instances.